Multi-data analysis power distribution terminal control system and method

Abstract

The invention discloses a power distribution terminal control system and method based on multi-data analysis, and relates to the technical field of smart power grids. The system integrates a multi-data acquisition module, a parameter management module, a fault analysis decision module, an execution control module and a communication interaction module; the multi-data acquisition module collects electrical quantity and switch position signals, and the parameter management module provides basic data support; the fault analysis decision-making module analyzes FTU types and fault types in sequence to generate differentiation strategies, switching operation is executed through the execution control module, and information sharing and collaboration are achieved through the communication interaction module; according to the system, through dynamic FTU type identification, a precise fault processing mechanism and multi-source data deep fusion, the problems of data island, single fault processing strategy and insufficient multi-source data fusion in a traditional power distribution automation system are solved, the power supply reliability is improved, the manual configuration workload is reduced, and the equipment damage risk is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of smart grids, and specifically to a distribution terminal control system and method for multi-data analysis. Background Art

[0002] With the rapid development of smart grids, distribution network automation technology has become the core means to improve power supply reliability. However, traditional distribution automation systems still face the following technical bottlenecks: 1. Data islands and static configuration dependence: The independent construction of marketing, distribution, and dispatching systems leads to data fragmentation. Equipment types need to be predefined manually, and reconfiguration is required during network reconstruction, making it difficult to adapt to the dynamic scenarios of large-scale access of distributed power sources.

[0003] 2. Single fault handling strategy: The same closing strategy is adopted for both head-end and non-head-end devices, which is likely to cause mispower outage in non-fault areas, and there is a lack of continuous monitoring mechanism after closing, which may lead to the expansion of permanent faults.

[0004] 3. Insufficient multi-source data fusion: The distribution automation master station relies on single SCADA measurements and cannot effectively integrate the power consumption information acquisition system, limiting the real-time performance and accuracy of advanced application analysis. Summary of the Invention

[0005] The purpose of the present invention is to provide a distribution terminal control system and method for multi-data analysis to solve the problems raised in the prior art.

[0006] To achieve the above purpose, the present invention provides the following technical solutions: A distribution terminal control system based on multi-data analysis includes a multi-data acquisition module, a parameter management module, a fault analysis and decision-making module, an execution control module, and a communication interaction module; the multi-data acquisition module is responsible for real-time acquisition of three-phase current, zero-sequence current, voltage, and switch position signals of the distribution circuit to provide basic data for fault analysis; the parameter management module is responsible for storing, configuring, and maintaining static parameters related to equipment operation to provide basic data for fault analysis, protection action, and communication interaction; the fault analysis and decision-making module analyzes the FTU type and fault type based on various data collected by the multi-data acquisition module and generates a differentiated control strategy; the control execution module performs switch opening and closing operations according to the instructions of the decision-making module and feeds back the execution results; the communication interaction module is used to achieve fault information sharing between FTUs and communicate with the master station to ensure multi-terminal collaborative fault handling.

[0007] The multi-data acquisition module includes an electrical quantity data acquisition unit and a switch position signal acquisition unit; The electrical quantity data acquisition unit obtains the three-phase current and zero-sequence current signals of the distribution circuit through current transformers, and obtains the line voltage signal through a voltage transformer. Then, the analog signals output by the transformers are input into the signal conditioning circuit for amplification and filtering to eliminate noise interference and stabilize the signal amplitude and phase. Finally, the analog-to-digital conversion circuit is used to digitally convert the conditioned analog signals at a preset sampling frequency and output standard digital signals for use by the subsequent fault analysis and decision-making module. The switch position signal acquisition unit is responsible for obtaining the status signals of the switch open position and closed position in real time, thereby judging the current operating state of the switch, assisting in fault location analysis, and providing information on whether the switch operation is successful for the system. The implementation method is as follows: First, through hardware connection, the auxiliary contacts that are synchronously switched with the opening and closing actions of the switch body are connected to the acquisition unit circuit. Then, the opto-coupler circuit is used to convert the mechanical on-off signal of the auxiliary contacts into a standard electrical signal to achieve isolation between high voltage and low voltage. Finally, the microcontroller of the acquisition unit reads the converted electrical signal in real time, converts it into a digital quantity, stores it, and transmits it to the fault analysis and decision-making module for system analysis.

[0008] The parameter management module includes a parameter storage unit, a parameter configuration unit, a parameter verification unit, a parameter synchronization unit, and a parameter security management unit. The parameter storage unit uses EEPROM to store the inherent parameters and operating parameters of the terminal. The parameter configuration unit is responsible for providing local and master station parameter configuration interfaces, supporting operations such as adding, deleting, modifying, and querying parameters, and verifying the legality of the input parameters. The parameter verification unit is used to verify the parameter format and check for parameter conflicts. The parameter synchronization unit is responsible for realizing the two-way synchronization of parameters between the master station and the terminal, supporting automatic uploading and receiving of parameter changes, and recording the parameter modification log. The parameter security management unit is responsible for controlling parameter modification based on permission grading and preventing unauthorized access.

[0009] The fault analysis and decision-making module includes an FTU type analysis unit, a fault type analysis unit, and a strategy generation unit. The FTU type analysis unit analyzes whether the current FTU is a head-end FTU or a non-head-end FTU according to the distribution network topology configuration information, providing a basis for the differential control strategy. Specifically: First, the parameter management module provides static configuration parameters such as the terminal ID, PT primary rated value, head-end FTU input flag, and zero-sequence CT ratio. At the same time, it receives the zero-sequence current amplitude and voltage phase information collected in real time by the multi-data acquisition module. Then, type determination is performed through a dual logic of address matching and parameter verification. The head-end FTU needs to satisfy both the head-end flag being 1, the ID matching the predefined node of the master station, and the PT rated value conforming to the substation bus voltage level. For the non-head-end FTU, when the head-end flag is 0 or the ID does not match, through a differential parameter design where the zero-sequence CT primary rated value is 50% higher than the head-end configuration, it adapts to the small current detection requirements in the high-impedance grounding scenario at the end of the line. Finally, when an ID conflict is detected or the deviation between the PT rated value and the measured voltage exceeds 10%, an alarm is triggered. When a parameter is missing, it is automatically degraded to the non-head-end mode, thus realizing intelligent type recognition based on the dynamic characteristics of the distribution network. The fault type analysis unit uses the transient waveform data of the zero-sequence current 3I0 and zero-sequence voltage 3U0 obtained in real time by the multi-data acquisition module, applies the fast Fourier transform to extract the high-frequency components in the frequency band of 100Hz - 500Hz, and then calculates the sudden change amplitude ΔI0 of the zero-sequence current. The calculation formula is as follows: ; Among them, 3I0 is the sum of the three-phase currents, 3U0 is the sum of the three-phase voltages, I0(t) represents the effective value of the zero-sequence current at the current sampling point, and I 0steady represents the steady-state zero-sequence current effective value; when ΔI0 > 0.5A and the duration is greater than 20ms, it is determined as a ground fault; At the same time, based on the voltage phase information, the phase difference ψ between the zero-sequence current and the zero-sequence voltage is calculated. The calculation formula is as follows: ; Among them, Im represents the imaginary part, Re represents the real part. When , it is determined as a forward ground fault, that is, a fault on this line; when , it is determined as a reverse ground fault, that is, a fault not on this line; For phase-to-phase short-circuit faults, the three-phase current amplitudes are monitored. When and are satisfied, it is determined as a phase-to-phase short circuit; among them represents the overcurrent I-section setting value, represents the zero-sequence I-section setting value; through the above determination method, the fault type and direction are identified, providing a basis for the subsequent differential control strategy; Based on the fault type and fault direction output by the fault type analysis unit, and in combination with the FTU type provided by the parameter management module, the strategy generation unit generates a differential control strategy and drives the execution control module to implement it.

[0010] The strategy generation unit further includes the following: Based on the fault type and fault direction output by the fault type analysis unit, and in combination with the FTU type provided by the parameter management module, the strategy generation unit generates a differential control strategy and drives the execution control module to implement it; specifically divided into the head-end FTU strategy, non-head-end FTU strategy, and locking and reclosing strategy; For the head-end FTU strategy, for single-phase grounding faults, when the fault direction is positive, that is at this time, the zero-sequence I-section protection is started and tripped by the line selection tripping time; if the zero-sequence voltage 3U0 is greater than the zero-sequence voltage setting value within the Y time after closing, trip and block the reclosing; for phase-to-phase short-circuit faults, the overcurrent I-section protection is started for instantaneous tripping and closed after the reclosing confirmation time; For the non-head-end FTU strategy, for single-phase grounding faults, when the detected zero-sequence current 3I0 is greater than the zero-sequence I-section setting value, close after X time. If there is no fault within the Y time after closing, that is, 3U0 < zero-sequence voltage setting value and 3I0 < zero-sequence current I-section setting value, start the long-time delay closing of S time; for phase-to-phase short-circuit faults, when the overcurrent II-section setting value is detected, close after X time; if there is no fault within the Y time after closing, that is, each phase current < overcurrent I-section setting value, confirm successful reclosing; For the locking and reclosing strategy, if a fault is detected within the Y time after closing, that is, the zero-sequence voltage > setting value, trigger the closing-after zero-sequence overvoltage protection to trip and block the reclosing; after the fault is eliminated, automatically reclosing according to the signal automatic reclosing time of the parameter management module or the master station command, and resume the normal operation state.

[0011] The execution control module includes an operation execution unit and a feedback unit; The operation execution unit is responsible for receiving the opening and closing commands of the fault analysis and decision-making module, including tripping by the line selection tripping time and closing after X time, and driving the switch operating mechanism coil through a solid-state relay. Specifically: for the opening operation, trigger the opening coil and disconnect after the opening pulse time; for the closing operation, trigger the closing coil and disconnect after the closing pulse time; at the same time, this unit has a hardware anti-misoperation design, and the continuous two command times need to be separated by a preset time to avoid misoperation; The feedback unit collects the switch auxiliary contact signal and the energy storage state of the operating mechanism through an optocoupler, converts the state into a digital quantity, and then feeds it back to the fault analysis and decision-making module. If no state feedback is received within the preset time after the action, an operation failure alarm is triggered. Specifically: after receiving the instruction, the closing or tripping coil is triggered according to the type, and the switch state is monitored synchronously. If successful, the state record SOE event is updated; if failed, an alarm is triggered and subsequent operations are blocked to ensure the closed-loop control of action execution and state feedback.

[0012] The communication interaction module includes a data sending unit and a data receiving unit; The data sending unit obtains the fault type, FTU type, and control strategy from the fault analysis and decision-making module; obtains the switch action result from the execution control module; reads the real-time electrical quantity data from the multi-data acquisition module; and then packs and sends the local fault analysis results, control strategy, switch state, and operation parameters to the master station and adjacent FTUs. The function of the data receiving unit is to receive and parse the control instructions, parameter configurations, and time synchronization commands issued by the master station, and at the same time receive the fault information of adjacent FTUs to achieve multi-terminal collaborative control. Specifically: in terms of data listening, it listens for the master station connection request through the default port and detects the link state. If the master station communication is interrupted, the unuploaded TCOS events are locally cached and preferentially uploaded after the communication is restored; in terms of instruction parsing, it parses the remote control command, verifies the operation authority through the security chip authentication, and at the same time parses the parameter configuration instruction and calls the parameter management module to update the configuration; in terms of instruction execution, it forwards the remote control instruction to the execution control module to trigger the switch action and synchronizes the time synchronization command to the system clock to ensure that the time error between the device and the master station does not exceed the threshold range.

[0013] A distribution terminal control method for multi-data analysis includes the following steps: S1. The multi-data acquisition module monitors the three-phase current and zero-sequence current in real time through current transformers, and monitors the line voltage through voltage transformers. When the phase current exceeds the instantaneous trip protection setting value or the zero-sequence current exceeds the zero-sequence I-section setting value, or the voltage suddenly drops to the low-voltage setting value, the fault detection mechanism is triggered; at this time, the multi-data acquisition module encapsulates the fault type and direction standard into a file, uploads it to the master station through the communication interaction module, and simultaneously sends a fault trigger signal to the fault analysis and decision-making module. S2. The fault analysis and decision-making module makes a type determination based on the terminal ID, PT primary rated value, and the first-end FTU input flag provided by the parameter management module, combined with the real-time data of the multi-data acquisition module: if the first-end flag is 1 and the ID matches the master station predefined first-end node, and at the same time the PT rated value conforms to the substation bus voltage level, it is determined as the first-end FTU; otherwise, it is verified through the zero-sequence CT ratio to adapt to the high-impedance grounding scenario at the end of the line; if there is a parameter conflict, it is defaulted to be downgraded to a non-first-end and a log is recorded. S3. For the head-end FTU, calculate the phase difference ψ between the zero-sequence current and voltage through the zero-sequence directional line selection algorithm. When it is determined that the fault is on this line, the zero-sequence I-section protection is started to trip after the line selection tripping time; in the case of phase-to-phase short circuit, the phase current > the overcurrent I-section setting value and 3I0 < the zero-sequence I-section setting value, trip instantaneously and then close the switch after the reclosing confirmation time; S4. For non-head-end FTUs, if the detected phase current > the overcurrent II-section setting value, generate a closing command for X time; if 3I0 > the zero-sequence I-section setting value, generate a closing command for S time, and achieve fault isolation through a differential delay strategy; S5. The operation execution unit receives the instructions from the fault analysis and decision-making module and drives the switch operating mechanism through a solid-state relay: trigger the tripping coil when tripping and the closing coil when closing; the head-end FTU closes the switch after the line selection reclosing time, and the non-head-end FTU executes the closing for X time or S time according to the fault type; the operation execution unit has an anti-misoperation mechanism built in, and consecutive commands need to be spaced more than the preset time range to ensure safe operation; S6. After the closing is completed, the multi-data acquisition module continuously monitors the electrical quantities within Y time. If 3U0 < the zero-sequence voltage setting value and the phase current < the overcurrent I-section setting value, it is confirmed that the reclosing is successful; if the zero-sequence voltage exceeds the limit or the current exceeds the limit is detected, trigger the post-closing zero-sequence overvoltage protection to trip and block the reclosing; the feedback unit collects the switch auxiliary contact signal through an optocoupler, and if the status feedback is not received within the preset time threshold, trigger an operation failure alarm; S7. After the fault is eliminated, the parameter management module restores the system status according to the automatic restoration time or the master station command, and resets the fault flag; the communication interaction module uploads the fault event and the waveform recording file to the master station, the master station updates the terminal parameters, and synchronizes them to the parameter management module through the authentication of the security chip to ensure the consistency of the system parameters.

[0014] Compared with the prior art, the beneficial effects of the present invention are: 1. Dynamic FTU type identification: Based on terminal ID matching, PT rated value verification, and zero-sequence CT ratio difference, automatically identify the head-end / non-head-end FTU, support plug-and-play, and reduce the manual configuration workload.

[0015] 2. Precise fault handling mechanism: The head-end FTU adopts the zero-sequence directional line selection algorithm, trips instantaneously and starts differential reclosing; the non-head-end FTU identifies the fault type through the transient current mutation characteristics, generates X / S time closing commands, and shortens the fault handling time to the second level; the Y-time monitoring mechanism after closing triggers the blocking to avoid reclosing for permanent faults and reduce the risk of equipment damage.

[0016] 3. Deep integration of multi-source data: The system real-time integrates three-phase current, zero-sequence current, voltage, and switch position signals through a multi-data acquisition module, and constructs a fault analysis model based on transient characteristics in combination with the static parameters of the parameter management module; extracts high-frequency components through fast Fourier transform to accurately calculate the mutation and phase difference of zero-sequence current, and supports the generation of differential control strategies for the head-end / non-head-end FTU. The communication interaction module realizes the sharing of multi-terminal fault information, and at the same time ensures the reliability of the control strategy through dynamic parameter verification. Description of the Drawings

[0017] Figure 1 It is a schematic flow chart of the control method of a distribution terminal control method based on multi-data analysis according to the present invention; Figure 2 It is a schematic diagram of the system architecture of a distribution terminal control system based on multi-data analysis according to the present invention. Detailed Embodiments

[0018] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0019] Embodiment: As Figure 1 - Figure 2 shown, the present invention provides a technical solution, A distribution terminal control system based on multi-data analysis includes a multi-data acquisition module, a parameter management module, a fault analysis and decision-making module, an execution control module, and a communication interaction module; the multi-data acquisition module is responsible for real-time collecting three-phase current, zero-sequence current, voltage, and switch position signals of the distribution circuit to provide basic data for fault analysis; the parameter management module is responsible for storing, configuring, and maintaining static parameters related to equipment operation to provide basic data for fault analysis, protection action, and communication interaction; the fault analysis and decision-making module analyzes the FTU type and fault type based on various data collected by the multi-data acquisition module to generate differential control strategies; the control execution module performs switch opening and closing operations according to the instructions of the decision-making module and feedbacks the execution results; the communication interaction module is used to realize the sharing of fault information between FTUs and communicate with the master station to ensure the collaborative processing of faults by multiple terminals.

[0020] The multi-data acquisition module includes an electrical quantity data acquisition unit and a switch position signal acquisition unit; The electrical quantity data acquisition unit obtains the three-phase current and zero-sequence current signals of the distribution circuit through a current transformer, and obtains the line voltage signal through a voltage transformer. Then, the analog signal output by the transformer is input into the signal conditioning circuit for amplification and filtering to eliminate noise interference and stabilize the signal amplitude and phase. Finally, the analog-to-digital conversion circuit is used to digitally convert the conditioned analog signal at a preset sampling frequency and output a standard digital signal for use by the subsequent fault analysis and decision-making module. The switch position signal acquisition unit is responsible for obtaining the status signals of the switch open position and closed position in real time, thereby judging the current operating state of the switch, assisting in fault location analysis, and providing information on whether the switch operation is successful for the system. The implementation method is as follows: First, through hardware connection, the auxiliary contacts that are synchronously switched with the opening and closing actions of the switch body are connected to the acquisition unit circuit. Then, the opto-coupler circuit is used to convert the mechanical on-off signal of the auxiliary contacts into a standard electrical signal to achieve isolation between strong electricity and weak electricity. Finally, the microcontroller of the acquisition unit reads the converted electrical signal in real time, converts it into a digital quantity, stores it, and transmits it to the fault analysis and decision-making module for system analysis.

[0021] The parameter management module includes a parameter storage unit, a parameter configuration unit, a parameter verification unit, a parameter synchronization unit, and a parameter security management unit. The parameter storage unit uses EEPROM to store the inherent parameters and operating parameters of the terminal. The parameter configuration unit is responsible for providing local and master station parameter configuration interfaces, supporting operations such as adding, deleting, modifying, and querying parameters, and verifying the legality of the input parameters. The parameter verification unit is used to verify the parameter format and check for parameter conflicts. The parameter synchronization unit is responsible for realizing the two-way synchronization of parameters between the master station and the terminal, supporting the automatic uploading and receiving of parameter changes, and recording the parameter modification log. The parameter security management unit is responsible for controlling parameter modification based on permission levels and preventing unauthorized access.

[0022] The fault analysis and decision-making module includes an FTU type analysis unit, a fault type analysis unit, and a strategy generation unit. The FTU type analysis unit analyzes whether the current FTU is a head-end FTU or a non-head-end FTU according to the distribution network topology configuration information, providing a basis for the differential control strategy. Specifically: First, the parameter management module provides static configuration parameters such as the terminal ID, the rated primary value of the PT, the head-end FTU input flag, and the zero-sequence CT ratio. At the same time, it receives the zero-sequence current amplitude and voltage phase information collected in real time by the multi-data acquisition module. Then, type determination is performed through a dual logic of address matching and parameter verification. The head-end FTU needs to simultaneously meet the conditions that the head-end flag is 1, the ID matches the predefined node of the master station, and the PT rated value conforms to the substation bus voltage level. For the non-head-end FTU, when the head-end flag is 0 or the ID does not match, through a differential parameter design where the zero-sequence CT primary rated value is 50% higher than the head-end configuration, it adapts to the small current detection requirements in the high-impedance grounding scenario at the end of the line. Finally, when an ID conflict is detected or the deviation between the PT rated value and the measured voltage exceeds 10%, an alarm is triggered. When a parameter is missing, it automatically degrades to the non-head-end mode, thus realizing intelligent type recognition based on the dynamic characteristics of the distribution network. The fault type analysis unit uses the transient waveform data of the zero-sequence current 3I0 and zero-sequence voltage 3U0 obtained in real time by the multi-data acquisition module, applies the fast Fourier transform to extract the high-frequency components in the frequency band of 100Hz - 500Hz, and then calculates the zero-sequence current mutation amplitude ΔI0. The calculation formula is as follows: ; Among them, 3I0 is the sum of the three-phase currents, 3U0 is the sum of the three-phase voltages, I0(t) represents the effective value of the zero-sequence current at the current sampling point, and I 0steady represents the effective value of the steady-state zero-sequence current. When ΔI0 > 0.5A and the duration is greater than 20ms, it is determined as a ground fault; At the same time, based on the voltage phase information, the phase difference ψ between the zero-sequence current and the zero-sequence voltage is calculated. The calculation formula is as follows: ; Among them, Im represents the imaginary part, Re represents the real part. When , it is determined as a forward ground fault, that is, a fault on this line. When , it is determined as a reverse ground fault, that is, a fault on a non-this line; For phase-to-phase short-circuit faults, the three-phase current amplitudes are monitored. When and are satisfied, it is determined as a phase-to-phase short circuit. Among them, represents the overcurrent I-section setting value, represents the zero-sequence I-section setting value. Through the above determination method, the fault type and direction are identified, providing a basis for the subsequent differential control strategy; The strategy generation unit generates a differentiated control strategy based on the fault type and fault direction output by the fault type analysis unit, in combination with the FTU type provided by the parameter management module, and drives the execution control module to implement it.

[0023] The strategy generation unit further includes the following: The strategy generation unit generates a differentiated control strategy based on the fault type and fault direction output by the fault type analysis unit, in combination with the FTU type provided by the parameter management module, and drives the execution control module to implement it; specifically divided into the head-end FTU strategy, non-head-end FTU strategy, and locking and reclosing strategy; For the head-end FTU strategy, for single-phase grounding faults, when the fault direction is positive, that is when, start the zero-sequence I-section protection and trip through the line selection tripping time; if the zero-sequence voltage 3U0 is detected to be greater than the zero-sequence voltage setting value within the Y time after closing, trip and block the reclosing; for phase-to-phase short-circuit faults, start the overcurrent I-section protection and trip instantaneously, and close the switch after the reclosing confirmation time; For the non-head-end FTU strategy, for single-phase grounding faults, when the zero-sequence current 3I0 is detected to be greater than the zero-sequence I-section setting value, close the switch after the X time; if there is no fault within the Y time after closing, that is, 3U0 < zero-sequence voltage setting value and 3I0 < zero-sequence current I-section setting value, start the long-time delay closing of the S time; for phase-to-phase short-circuit faults, when the overcurrent II-section setting value is detected, close the switch after the X time; if there is no fault within the Y time after closing, that is, the current of each phase < overcurrent I-section setting value, confirm successful reclosing; For the locking and reclosing strategy, if a fault is detected within the Y time after closing, that is, the zero-sequence voltage > setting value, trigger the closing-after zero-sequence overvoltage protection to trip and block the reclosing; after the fault is eliminated, automatically reset according to the signal automatic reset time of the parameter management module or the master station command, and restore to the normal operation state.

[0024] The execution control module includes an operation execution unit and a feedback unit; The operation execution unit is responsible for receiving the opening and closing commands of the fault analysis and decision-making module, including tripping through the line selection tripping time and closing after the X time, and driving the switch operating mechanism coil through a solid-state relay. Specifically: for the opening operation, trigger the opening coil and disconnect after the opening pulse time; for the closing operation, trigger the closing coil and disconnect after the closing pulse time; at the same time, this unit has a hardware anti-misoperation design, and the continuous two command times need to be separated by a preset time to avoid misoperation; The feedback unit collects the switch auxiliary contact signal and the energy storage state of the operating mechanism through an optocoupler, converts the state into a digital quantity and then feeds it back to the fault analysis and decision-making module. If no state feedback is received within the preset time after the action, an operation failure alarm is triggered. Specifically: after receiving the instruction, the closing or opening coil is triggered according to the type, the switch state is monitored synchronously. If successful, the state record SOE event is updated; if failed, an alarm is triggered and subsequent operations are blocked to ensure the closed-loop control of action execution and state feedback.

[0025] The communication interaction module includes a data sending unit and a data receiving unit; The data sending unit obtains the fault type, FTU type and control strategy from the fault analysis and decision-making module; obtains the switch action result from the execution control module; reads the real-time electrical quantity data from the multi-data acquisition module; and then packs and sends these data such as the local fault analysis result, control strategy, switch state and operation parameters to the master station and adjacent FTUs. The function of the data receiving unit is to receive and analyze the control instructions, parameter configurations and time synchronization commands issued by the master station, and at the same time receive the fault information of adjacent FTUs to achieve multi-terminal collaborative control. Specifically: in terms of data listening, it listens for the master station connection request through the default port and detects the link state. If the master station communication is interrupted, the unuploaded TCOS events are cached locally and uploaded preferentially after the communication is restored; in terms of instruction analysis, it analyzes the remote control command, verifies the operation permission through the security chip authentication, and at the same time analyzes the parameter configuration instruction and calls the parameter management module to update the configuration; in terms of instruction execution, it forwards the remote control instruction to the execution control module to trigger the switch action and synchronizes the time synchronization command to the system clock to ensure that the time error between the device and the master station does not exceed the threshold range.

[0026] A control method for a distribution terminal with multi-data analysis includes the following steps: S1. The multi-data acquisition module monitors the three-phase current and zero-sequence current in real time through current transformers, and monitors the line voltage through voltage transformers. When it detects that the phase current exceeds the instantaneous protection setting value or the zero-sequence current exceeds the zero-sequence I-section setting value, or the voltage suddenly drops to the low-voltage setting value, the fault detection mechanism is triggered; at this time, the multi-data acquisition module encapsulates the fault type and direction standard into a file, uploads it to the master station through the communication interaction module, and simultaneously sends a fault trigger signal to the fault analysis and decision-making module; S2. The fault analysis and decision-making module makes a type determination based on the terminal ID, PT primary rated value and the first-end FTU input flag provided by the parameter management module, combined with the real-time data of the multi-data acquisition module: if the first-end flag is 1 and the ID matches the predefined first-end node of the master station, and at the same time the PT rated value conforms to the substation bus voltage level, it is determined as the first-end FTU; otherwise, through the zero-sequence CT ratio verification, it adapts to the high-impedance grounding scenario at the end of the line; if there is a parameter conflict, it is defaulted to be downgraded to a non-first-end and a log is recorded. S3. For the head-end FTU, calculate the phase difference ψ between the zero-sequence current and voltage through the zero-sequence directional line selection algorithm. When it is determined that the fault is on this line, start the zero-sequence I-section protection and trip after the line selection tripping time; in the case of phase-to-phase short circuit, the phase current > the overcurrent I-section setting value and 3I0 < the zero-sequence I-section setting value, trip immediately and then close after the reclosing confirmation time; S4. For non-head-end FTUs, if the detected phase current > the overcurrent II-section setting value, generate a closing command for X time; if 3I0 > the zero-sequence I-section setting value, generate a closing command for S time, and achieve fault isolation through the differential delay strategy; S5. The operation execution unit receives the instructions from the fault analysis and decision-making module and drives the switch operating mechanism through a solid-state relay: trigger the tripping coil when tripping and the closing coil when closing; after the head-end FTU trips, close after the line selection reclosing time, and the non-head-end FTU closes for X time or S time according to the fault type; the operation execution unit has an anti-misoperation mechanism built in, and consecutive instructions need to be spaced more than the preset time range to ensure safe operation; S6. After closing is completed, the multi-data acquisition module continuously monitors the electrical quantities within Y time. If 3U0 < the zero-sequence voltage setting value and the phase current < the overcurrent I-section setting value, confirm successful reclosing; if it is detected that the zero-sequence voltage exceeds the limit or the current exceeds the limit, trigger the post-closing zero-sequence overvoltage protection to trip and block the reclosing; the feedback unit collects the switch auxiliary contact signals through an optocoupler, and if the status feedback is not received within the preset time threshold, trigger an operation failure alarm; S7. After the fault is eliminated, the parameter management module restores the system status according to the automatic restoration time or the main station's instructions, and resets the fault flag; the communication interaction module uploads the fault event and the waveform file to the main station, the main station updates the terminal parameters, and synchronizes them to the parameter management module through the authentication of the security chip to ensure the consistency of the system parameters.

[0027] Embodiment: A single-phase grounding fault occurs on a 10 kV distribution network line (the head-end FTU number is 0x01, and the zero-sequence CT transformation ratio is 20 / 5 A). The system realizes fault handling through the following process: The multi-data acquisition module monitors the line electrical quantities in real time at a sampling rate of 128 points / cycle. When it detects that the zero-sequence current 3I0 = 120 A (exceeding the zero-sequence I-section setting value 0x824B = 100 A) and lasts for 25 ms, and at the same time the zero-sequence voltage 3U0 = 6 kV (exceeding the zero-sequence voltage setting value 0x8022 = 5 kV), trigger fault detection; the module automatically records the waveform data of the previous 4 cycles and the subsequent 8 cycles before the fault, encapsulates them according to the Comtrade 1999 standard, uploads them to the main station through the IEC104 port, and sends a trigger signal to the fault analysis and decision-making module.

[0028] Based on the terminal ID provided by the parameter management module (0x01 matches the predefined head node of the master station), the PT rated value (0x8026 = 10 kV), and the zero-sequence CT transformation ratio (0x8042 = 20 / 5 A), the fault analysis and decision-making module dynamically verifies in combination with real-time data: when the head flag is 1, the ID matches, and the deviation between the PT rated value and the measured voltage is < 10%, it is determined as the head FTU; the phase difference ψ is calculated through the zero-sequence direction selection algorithm. Assuming the real part Re of 3U0 is 5.5 kV, the imaginary part Im is 3.2 kV, the real part Re of 3I0 is 100 A, and the imaginary part Im is 80 A, then ψ = 30° - 38.7° = -8.7° (taking the absolute value, 8.7° ∈ (0°, -90°)), and it is determined as a forward fault.

[0029] The strategy generation unit activates the head FTU strategy: triggers the zero-time tripping of the zero-sequence I-section protection (0x824B) and closes the switch after the line selection reclosing time (0x8228 = 0.5 s). The adjacent non-head FTU (zero-sequence CT transformation ratio 50 / 5 A) detects that the phase current suddenly increases to 800 A (exceeding the overcurrent II-section setting value 0x8247 = 600 A) and generates a closing command for X time (0x8224 = 2 s). The execution control module drives the switch operating mechanism through a solid-state relay, with a tripping pulse time of 0x8031 = 200 ms and a closing pulse time of 0x8032 = 200 ms. The head FTU closes the switch after 0.5 s of tripping, and the non-head FTU closes the switch after 2 s.

[0030] Within Y time (0x8225 = 10 s) after closing, the multi-data acquisition module continuously monitors that 3U0 = 0.5 kV (< 5 kV) and the phase current = 200 A (< the overcurrent I-section setting value 0x8243 = 500 A) to confirm successful reclosing. After the master station receives the fault event and the waveform recording file, it updates the zero-sequence I-section setting value (0x824B = 100 A → 120 A) through the authentication of the security chip, and the parameter management module automatically restores the system state and resets the fault flag.

[0031] Implementation effect: The fault handling time is shortened from the traditional 30 minutes to 2 minutes, and the positioning accuracy rate reaches 99%, verifying the effectiveness of the differential control strategy based on multi-data fusion.

[0032] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic characteristics of the present invention, the present invention can be implemented in other specific forms. Therefore, in any regard, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claims involved.

Claims

1. A power distribution terminal control system based on multi-data analysis, characterized in that: It includes a multi-data acquisition module, a parameter management module, a fault analysis and decision module, an execution control module and a communication interaction module; the multi-data acquisition module is responsible for real-time acquisition of the three-phase current, zero-sequence current, voltage and switch position signal of the distribution circuit to provide basic data for fault analysis; the parameter management module is responsible for storing, configuring and maintaining static parameters related to equipment operation to provide basic data for fault analysis, protection action and communication interaction; The fault analysis and decision module analyzes the FTU type and fault type based on the multiple types of data collected by the multiple data collection module, and generates a differentiated control strategy; The control execution module executes the switch opening and closing operations according to the instructions of the decision module and feeds back the execution results; the communication interaction module is used to realize the fault information sharing between FTUs and communicate with the main station to ensure that multiple terminals collaboratively handle faults.

2. The power distribution terminal control system for multi-data analysis according to claim 1, characterized in that: The multi-data acquisition module includes an electrical quantity data acquisition unit and a switch position signal acquisition unit; The electrical quantity data acquisition unit obtains the three-phase current and zero-sequence current signals of the distribution circuit through the current transformer, obtains the line voltage signal through the voltage transformer, and then inputs the analog signal output by the transformer into the signal conditioning circuit for amplification and filtering, eliminates noise interference, and stabilizes the signal amplitude and phase; finally, the analog-to-digital conversion circuit is used to digitize the conditioned analog signal according to the preset sampling frequency, and outputs a standard digital signal for use by the subsequent fault analysis and decision module; The switch position signal acquisition unit is responsible for acquiring the status signals of the switch opening and closing positions in real time, so as to judge the current operating state of the switch, assist in fault location analysis, and provide the system with information on whether the switch action is successful; the implementation method is: first, through hardware connection, the auxiliary contacts of the switch body that switch synchronously with the opening and closing actions are connected to the acquisition unit circuit; then, the mechanical on-off signals of the auxiliary contacts are converted into standard electrical signals using a photoelectric coupling circuit to achieve isolation between strong and weak electricity; finally, the microcontroller of the acquisition unit reads the converted electrical signals in real time, converts them into digital quantities, stores them, and transmits them to the fault analysis and decision module for system analysis.

3. The power distribution terminal control system for multi-data analysis according to claim 1, characterized in that: The parameter management module includes a parameter storage unit, a parameter configuration unit, a parameter verification unit, a parameter synchronization unit and a parameter security management unit; The parameter storage unit uses EEPROM to store terminal inherent parameters and operating parameters; The parameter configuration unit is responsible for providing local and master station parameter configuration interfaces, supporting parameter addition, deletion, modification and query operations, and verifying the legitimacy of input parameters; The parameter checking unit is used to verify the parameter format and check parameter conflicts; The parameter synchronization unit is responsible for realizing bidirectional synchronization of master station and terminal parameters, supporting automatic sending and receiving of parameter changes, and recording parameter modification logs; The parameter security management unit is responsible for controlling parameter modification based on authority classification and preventing unauthorized access.

4. The power distribution terminal control system for multi-data analysis according to claim 1, characterized in that: The fault analysis decision module includes an FTU type analysis unit, a fault type analysis unit and a strategy generation unit; The FTU type analysis unit analyzes the current FTU as a head-end FTU and a non-head-end FTU according to the topology configuration information of the distribution network, and provides a basis for the differentiated control strategy. Specifically, first, the parameter management module provides static configuration parameters such as the terminal ID, the PT primary rated value, the head-end FTU input flag, and the zero-sequence CT ratio, and receives the zero-sequence current amplitude and voltage phase information collected in real time by the multi-data acquisition module. Then, the type is determined through the dual logic of address matching and parameter verification. The head-end FTU must simultaneously meet the requirements of the head-end flag being 1, the ID matching the predefined node of the master station, and the PT rated value meeting the substation bus voltage level. When the head-end flag of the non-head-end FTU is 0 or the ID does not match, the zero-sequence CT primary rated value is designed to be 50% higher than the head-end configuration through differentiated parameters, so as to adapt to the small current detection requirements in the high-impedance grounding scenario at the end of the line. Finally, when an ID conflict is detected or the PT rated value deviates from the measured voltage by more than 10%, an alarm is triggered, and when the parameter is missing, it is automatically downgraded to the non-head-end mode, thereby realizing intelligent type identification based on the dynamic characteristics of the distribution network. The fault type analysis unit obtains the transient waveform data of zero-sequence current 3I0 and zero-sequence voltage 3U0 in real time through the multi-data acquisition module, uses fast Fourier transform to extract the high-frequency components in the 100Hz-500Hz frequency band, and then calculates the zero-sequence current mutation amplitude ΔI0. The calculation formula is as follows: ； Among them, 3I0 is the sum of the three-phase currents, 3U0 is the sum of the three-phase voltages, I0(t) represents the effective value of the zero-sequence current at the current sampling point, and I 0steady Indicates the effective value of the steady-state zero-sequence current; when ΔI0>0.5A and the duration is greater than 20ms, it is determined to be a ground fault; At the same time, the phase difference ψ between the zero-sequence current and the zero-sequence voltage is calculated based on the voltage phase information. The calculation formula is as follows: ； Among them, Im represents the imaginary part, Re represents the real part, when , it is determined to be a forward grounding fault, that is, a fault on this line; when , it is determined to be a reverse ground fault, that is, it is not a fault of this line; For phase-to-phase short-circuit faults, the three-phase current amplitude is monitored. and When , it is determined to be a phase-to-phase short circuit; Indicates the overcurrent I stage constant value, Indicates the zero-sequence I-stage constant; through the above determination method, the fault type and direction are identified to provide a basis for subsequent differentiated control strategies; The strategy generation unit generates a differentiated control strategy based on the fault type and fault direction output by the fault type analysis unit and the FTU type provided by the parameter management module, and drives the execution control module to implement the strategy.

5. The multi-data analysis power distribution terminal control system according to claim 4 is characterized in that: The strategy generation unit further includes the following contents: The strategy generation unit generates differentiated control strategies based on the fault type and fault direction output by the fault type analysis unit and the FTU type provided by the parameter management module, and drives the execution control module to implement them; specifically, it is divided into the head-end FTU strategy, the non-head-end FTU strategy, and the blocking and reset strategy; The first-end FTU strategy, for a unidirectional ground fault, when the fault direction is positive, that is, When the zero-sequence I stage protection is started, the circuit breaker is opened after the line selection tripping time; if the zero-sequence voltage 3U0 is detected to be greater than the zero-sequence voltage setting value within Y time after closing, the circuit breaker is opened and the reclosing circuit breaker is locked; for phase-to-phase short-circuit fault, the overcurrent I stage protection is started, the circuit breaker is opened with zero time limit, and the circuit breaker is closed after the reclosing confirmation time; The non-head-end FTU strategy, for a unidirectional grounding fault, when it is detected that the zero-sequence current 3I0 is greater than the zero-sequence I-stage set value, the circuit breaker is closed after X time. If there is no fault within Y time after closing, that is, 3U0<zero-sequence voltage set value and 3I0<zero-sequence current I-stage set value, the long-delay closing of S time is started; for a phase-to-phase short-circuit fault, when the overcurrent II-stage set value is detected, the circuit breaker is closed after X time; if there is no fault within Y time after closing, that is, the current of each phase is <overcurrent I-stage set value, the reclosing is confirmed to be successful; The locking and resetting strategy detects a fault within Y time after closing, that is, when the zero-sequence voltage is greater than the set value, the post-closing zero-sequence overvoltage protection is triggered to open the circuit breaker and lock the reclosing circuit breaker; after the fault is eliminated, it automatically resets according to the signal of the parameter management module or the master station command to restore the normal operating state.

6. The power distribution terminal control system for multi-data analysis according to claim 1, characterized in that: The execution control module includes an operation execution unit and a feedback unit; The operation execution unit is responsible for receiving the opening and closing instructions of the fault analysis and decision module, including opening at the line tripping time and closing at the X time, and driving the switch operating mechanism coil through the solid-state relay. Specifically: for the opening operation, the opening coil is triggered and disconnected after the opening pulse time; for the closing operation, the closing coil is triggered and disconnected after the closing pulse time; at the same time, the unit has a hardware anti-misoperation design, and two consecutive instruction times need to be separated by a preset time to avoid misoperation; The feedback unit collects the auxiliary contact signal of the switch and the energy storage status of the operating mechanism through a photoelectric coupler, converts the status into a digital quantity and then feeds it back to the fault analysis and decision module. If no status feedback is received within a preset time after the action, an operation failure alarm is triggered; specifically: after receiving the instruction, the opening / closing coil is triggered according to the type, and the switch status is monitored synchronously. If successful, the status record SOE event is updated, and if failed, an alarm is triggered and subsequent operations are locked to ensure closed-loop control of action execution and status feedback.

7. The power distribution terminal control system for multi-data analysis according to claim 1, characterized in that: The communication interaction module includes a data sending unit and a data receiving unit; The data sending unit obtains the fault type, FTU type and control strategy from the fault analysis and decision module; Obtain switch action results from the execution control module; read real-time electrical quantity data from the multi-data acquisition module; then package local fault analysis results, control strategies, switch status and operating parameters and send them to the master station and adjacent FTUs; The function of the data receiving unit is to receive and parse the control instructions, parameter configuration and timing commands issued by the master station, and receive the fault information of the adjacent FTU to realize multi-terminal collaborative control; specifically: in terms of data monitoring, the master station connection request is monitored through the default port, and the link status is detected. If the master station communication is interrupted, the TCOS events that have not been sent will be locally cached and uploaded first after the communication is restored; In terms of command parsing, the remote control commands are parsed, the operation permissions are verified through security chip authentication, and the parameter configuration instructions are parsed and the parameter management module is called to update the configuration. In terms of command execution, the remote control commands are forwarded to the execution control module to trigger the switch action, and the timing commands are synchronized to the system clock to ensure that the time error between the device and the main station does not exceed the threshold range.

8. A distribution terminal control method for multi-data analysis, applied to a distribution terminal control system for multi-data analysis according to claims 1-7, characterized in that: The following steps are involved: S1. The multi-data acquisition module monitors the three-phase current and zero-sequence current in real time through the current transformer, and monitors the line voltage through the voltage transformer. When it is detected that the phase current exceeds the quick-break protection setting value or the zero-sequence current exceeds the zero-sequence I-stage setting value, or the voltage drops suddenly to the low voltage setting value, the fault detection mechanism is triggered; at this time, the multi-data acquisition module encapsulates the fault type and direction standard into a file, uploads it to the main station through the communication interaction module, and simultaneously sends a fault trigger signal to the fault analysis and decision module; S2, the fault analysis and decision module determines the type based on the terminal ID, PT primary rating and head-end FTU input flag provided by the parameter management module, combined with the real-time data of the multi-data acquisition module: if the head-end flag is 1 and the ID matches the predefined head-end node of the master station, and the PT rating meets the substation bus voltage level, it is determined to be the head-end FTU; otherwise, through the zero-sequence CT ratio verification, it adapts to the high-impedance grounding scenario at the end of the line; If the parameters conflict, the default is to downgrade to non-head end and record the log; S3, for the head-end FTU, the zero-sequence current and voltage phase difference ψ is calculated by the zero-sequence direction line selection algorithm. It is determined that the line is faulty, and the zero-sequence I-stage protection is started and the circuit breaker is opened after the selected line tripping time; in case of phase-to-phase short circuit, if the phase current is greater than the overcurrent I-stage setting value and 3I0 is less than the zero-sequence I-stage setting value, the circuit breaker is closed after the zero-time limit opening and the reclosing confirmation time; S4. For non-head-end FTU, if the detected phase current is greater than the overcurrent II stage setting, an X time closing instruction is generated; if 3I0 is greater than the zero sequence I stage setting, an S time closing instruction is generated, and fault isolation is achieved through a differentiated delay strategy; S5. The operation execution unit receives the command from the fault analysis and decision module and drives the switch operation mechanism through the solid-state relay: the opening coil is triggered when the switch is opened, and the closing coil is triggered when the switch is closed; the first-end FTU closes after the selected line coincidence time after opening, and the non-first-end FTU closes after the X time or S time according to the fault type; the operation execution unit has a built-in anti-malfunction mechanism, and the interval between continuous commands must be greater than the preset time range to ensure safe operation; S6. After the closing is completed, the multi-data acquisition module continuously monitors the electrical quantity within the Y time. If 3U0 < zero-sequence voltage setting value and phase current < overcurrent I section setting value, the reclosing is confirmed to be successful; if the zero-sequence voltage exceeds the limit or the current exceeds the limit, the post-closing zero-sequence overvoltage protection is triggered to open and lock the reclosing switch; The feedback unit collects the auxiliary contact signal of the switch through a photoelectric coupler. If no status feedback is received within the preset time threshold, an operation failure alarm is triggered; S7. After the fault is eliminated, the parameter management module restores the system status according to the automatic reset time or the master station instruction and resets the fault flag; the communication interaction module uploads the fault event and the recording file to the master station, the master station updates the terminal parameters and synchronizes them to the parameter management module through security chip authentication to ensure the consistency of system parameters.

Images